"Our task must be to free ourselves by widening our circle of compassion to embrace all living creatures and the whole of nature and its beauty." Albert Einstein
What Are Marine Mammals?
Starting with the field of biology, I searched for a legal definition of marine mammals and/or marine animals. In order to understand marine mammals, we first need to understand what constitutes marine mammals. I found a definition of marine mammals at The Marine Mammal Centre as previous government legislation revoked the definition in a broader concept to instead define specific species.
The Marine Mammal Centre (n.d.) defines marine mammals as:
- animals that rely on the ocean for their existence
- have a wide variety of taxa, habitat and behavior
- some being fully aquatic
- others depend on the ocean for food
- provide a vital role in balancing marine ecosystems
- control prey populations
Marine Mammal Groups
Marine mammals include many groups which provides a greater understanding of the life that exists in the oceans. While we can not see these mammals on a regular basis, there are numerous species assisting the marine ecosystem.
There are 129 marine mammal species, including 88 cetaceans (Moss, 2017), meaning “sea monster” coming from the ancient Greek word “ketos” (Wang, 2013), including:
- 86 species of whales (14 of which are baleen whales)
- dolphins and porpoises (Perrin, 2019)
- 4 sirenians (dugongs and manatees)
- 34 pinnipeds (seals, walrus and sea lions)
- polar bears
- 2 sea otters species (a rare marine otter and a more common Pacific sea otter) (Moss, 2017).
Habitat and Food Source
According to Moss (2017):
- Cetaceans and sirenians live in the water.
- Pinnipeds, polar bears and sea otters haul out of water onto land or ice to rest, feed inshore or breed.
- Grey whales and walruses are sea floor invertivores.
- Balaenopterid whales are batch feeders on plankton and small schooling fish.
- Most pinnipeds and some cetaceans are intermediate carnivores.
- Killer whales and polar bears are apex carnivores
- Manatees are herbivores.
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Credits:
Created with images by Andrew Bain - "Dive! Pacific humpback whale tail (flukes)..." • Bart van meele - "Orcas gliding through the fjord under the light of the golden hour" • Andrew Bain - "Vanishing Flukes. Northern Pacific humpback..." • darin ashby - "Vacation in Cozumel" • Kris Mikael Krister - "The Dugongs of Marsha Shouna (Dugong dugon) Dugongs are believed to be inspirations behind tales of mermaids and in parts of Indonesia they are considered reincarnations of women. The word "dugong" means lady of the sea. It's herbivorous and feed uniquely on sea grass. Their numbers are very low and in some countries they are entirely depleted due to hunting, bycatch and habitat destruction. I was extremely lucky to encounter one in Marsha Shouna on the western coast of the Red Sea, once home to thousands of dugongs but now with very few individuals. The 100 km coastline along Marsa Alam had only seven dugongs left at the time of writing." • NOAA - "Mother manatee and calf swimming out of the inlet. " • Federico Artusi - "A couple of seals resting on an ice block. Shot in the bay of a glacier ending in the sea close to Juneau, the capital city of Alaska." • Jay Ruzesky - "untitled image" • Cibi Chakravarthi - "untitled image" • Brian McMahon - "untitled image" • Abigail Lynn - "untitled image" • Andres Corredor - "untitled image"